Calix[4]arene daisychains

Abstract

Generic calix[4]arenes became readily accessible in the late 70s. With their potential eight anchoring points, their utility for the production of sophisticated, highly functionalised macrocyclic molecules was rapidly recognised. While most studies in calixarene chemistry have focused on monocalixarene derivatives, there is now an increasing interest in developing multicalixarene compounds, especially those made of several linearly-arranged calix[4]arene units, the first examples of which were reported in 1989. This critical review will present the most important synthetic routes to such molecules together with an analysis of the properties that such cavity combinations may induce. In particular it will be shown that the nature of the links between the calixarene units plays a determinant role in the product properties and that singly-linked calixarenes can be exploited in varied applications, including those as efficient receptors of large molecules, as electrochemical and luminescent sensors in ion detection, or as new materials allowing capsule formation suitable for the storage of small guests (82 references).

Stimuli‐Responsive Polymeric Nanoparticles for Nanomedicine

“…For organic macrocycles, many examples exist that were created by a diverse set of bond‐forming methodologies. Classic macrocyclic species including crown ethers,9 β‐cyclodextrins,10 pillar[ n ]arenes,11 calix[ n ]arenes,12 and cucurbit[ n ]urils13 have been well documented and, hence, will not be discussed in this review. Some special species including shape‐persistent OMCs,14 conjugated macrocycles,2b, 15 multiporphyrinic cages,16 “blue box” [cyclobis(paraquat‐ p ‐phenylene)],17 bis(urea) macrocycles,18 boronic acid based OMCs,19, 67 and anion receptors20 have been thoroughly discussed in other review papers; thus, these types of OMCs will only be briefly represented herein with a few selected examples.…”

Systematic Structural Coordination Chemistry ofp‐tert‐Butyltetrathiacalix[4]arene: Main Group Metal Complexes Other Than Those of Group 1

“…[3][4][5][6][7][8][9][10][11][12][13][14][15][16] As synthetic macrocyclic ligands, the calixarenes are somewhat unusual in that the donor sites for metal ion binding are most commonly atoms within pendent substituents rather than within the macrocycle itself. There are parallels here with some naturally occurring "ionophores" [17] but only the relatively recent synthesis of calixarene systems in which sulfur replaces the methylene groups, those of the thiacalixarenes [18][19][20][21] (as well as mercaptothiacalixarenes [22,23] and thiacalixanilines [24,25] ), has provided materials which may be considered comparable to a wide range of macrocycles, both natural (e.g.…”

“…Nonetheless, there are reasons to believe that the thiacalixarenes and their derivatives may constitute a rather unique class of macrocycles [21,27] with unusual metal-binding properties. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46] A common feature of known calixarene and thiacalixarene chemistry is the formation of inclusion complexes, [3,4,23,27,37,47,48] and this, of course, may be considered as another form of "coordination" chemistry, [49] though the exact forces at work are difficult to identify and quantify, [47] especially as most precise data derive from solid-state structural determinations where both inter-and intra-molecular interactions may be involved. [47,…”

Pentakis-Amidothiacalix[4]arene Stereoisomers: Synthesis and Effect of Central Core Conformation on Their Aggregation Properties

“…In this regard, synthesis of multicalix [4] arenes, usually leads to mixtures of products or to low yields of the compound desired. To synthesize multicalixarenes, various reaction procedures such as O-alkylation, [26] crosscoupling of an olefin and alkynyl derivatives, [27][28][29] as well as linking calixarene units by forming amide and ester bond [30][31][32] have been described.…”